Parallel
Exodus 27:8
Swete's Septuagint · Berean Standard Bible
κοιλον σανιδωτὸν ποιήσεις αὐτό· κατὰ τὸ παραδειχθέν σοι ἐν τῷ ὄρει, οὕτως ποιήσεις αὐτό.
Construct the altar with boards so that it is hollow. It is to be made just as you were shown on the mountain.